package base64x import ( `fmt` `os` `github.com/klauspost/cpuid/v2` ) func hasAVX2() bool { switch v := os.Getenv("B64X_MODE"); v { case "" : fallthrough case "auto" : return cpuid.CPU.Has(cpuid.AVX2) case "noavx2" : return false default : panic(fmt.Sprintf("invalid mode: '%s', should be one of 'auto', 'noavx2'", v)) } }